Lumen rating Dr. LED "Sidekick" LED bulb E26 base

[erps]

So about half of my fixtures use a standard E-26 household type bulb. A few years ago, I changed them all out to CFL's, "looks funny/saves money" to save energy. They still draw 1.5 amps each, they're not as bright as I'd like and they take a while to warm up.

So now I'm looking at a Dr. LED bulb for the same fixtures. They're a 3 watt bulb and they say they're equivalent to a 60 watt bulb. So the lumen rating for a 60 watt bulb is around 800 lumens. The lumen rating for this bulb is 160. How can they claim it's a 60 watt equivalent when the lumens are less than 25% the lumen rating of an equivalent bulb? Is there something funny about lumens for LED bulbs? Anyone use one of these bulbs?

Dr. LED's Edison Screw Base LED Bulbs

[ebs001]

I can't find anything to suggest that lumens are any different for LEDs. Wiki gives a generic LED a rating of 100 lumens per watt. So a 3W LED would produce 300 lumens. A 60W incendecent gives 660 lumens on their chart. They were doing a cost comparison and listed a 9W LED. I would say that Dr. LED is wrong in their figures. Maybe the name should be Miss LED.

[Cruisingdad]

Hey Ray,

Maybe a totally different discussion and if off base, forgive me... but I converted (from Costco) to LEDs and CFL on 110v. Instead of using their 60w=60w equation, I converted up to a higher wattage and still save money. For example, lets say you have a 60w base. Instead of using their 60w replacement bulb, go up to 75 or 100w. You still save money and it really is a LOT brighter. You can also get the 110v stuff cheap at Costco. A simply inverter fixes 12v-110v issues and in the ned is probably cheaper.

Hope not too off base. Hope you are doing well too. ENjoying some nice weather I hope? It was 51 (high) when I left WA a month or so ago.

Brian

[erps]

Brian, the sun came out last week. If this keeps up, I may have tan knees before the end of July! I'm going to hold off a little while longer on the LED bulb replacements. At $30 to almost $40 a bulb, it's more than I want to spend to experiment with. Our solar panels keep us in plenty of power for our current boat use anyway. Wish I knew you guys were in our neighborhood a couple of months ago. Both JRD22 and I showed Bilgewater around when he came through on a boat delivery a couple months ago.

[simpsoned]

As a side note, have had bad luck with Dr LED for service on returns and have received some definitely "used" materials instead of new (like they just took someone elses return and sent it to me...ended up going with SuperbrightLEDs.com...had great service and prices were a lot lower. I am not sure about the lumen conversion, but I changes out my foremast light and spreader lights, plus all the interior ones and the boat is a lit brighter, plus I cut my power usage from 16.3 amps with all lights on to just over 6 amps with all lights on...
Ed Simpson
Newport 30 II #854
"I am the skipper...when my wife says so"

[Cruisingdad]

Originally Posted by erps

Brian, the sun came out last week. If this keeps up, I may have tan knees before the end of July! I'm going to hold off a little while longer on the LED bulb replacements. At $30 to almost $40 a bulb, it's more than I want to spend to experiment with. Our solar panels keep us in plenty of power for our current boat use anyway. Wish I knew you guys were in our neighborhood a couple of months ago. Both JRD22 and I showed Bilgewater around when he came through on a boat delivery a couple months ago.

My dad is in Olympia now on his Tayana 42. He and I may sail her up to GIg Harbor next week. He is keeping his boat there and cruising your side of the world. Get-together would be great sometime.

Brian

[JimsCAL]

Looks like your CFLs are drawing 18 watts (1.5 amps at 12V) so they should be roughly equivalent to a 60 watt incandescent bulb. An LED will be better, but not substantially. I note that Defender shows a Dr. LED bulb for an E26 fixture, but its 120VAC, not 12VDC. I switched most of my lights to Imtra replacement bulbs over the last three years, Tried a couple, was happy, then switched the rest. But they are bayonnet sockets, not the large screw base.

[hellosailor]

erps, as i understand it the problem is "let's confuse the customer with numbers".

Or was it the old Devo lyric, "he baffled me with science" ?

OK, if I've screwed this up someone please correct it.

Lumens reflect the brightness from a specific area. If you picture a shining white ball, a miniature sun hanging in the middle of your cabin, the light coming out of it can be measured in candela, or lumens, among other ways. Now draw a little circle or square on the surface of that sun. Measure the light coming out of that little circle. That's your lumens. Step back a few yards, hold up an incident light meter, see how much light is falling on it, and you've got candela. One is the emitted light from a specific spot, the other is the light falling on something away from the whole bulb. Under certain conditions, yes, the two will be the same. Or at least, have a linear relation. At other times, not.

Drop a towel over the back side of the sun, and your cabin now gets way dimmer. But wait, if you meaure that circle you drew again, the lumens haven't changed. Somehow, the lumens haven't changed but the sun got dimmer! And the candlepower measurement will be lower.

And there's your discrepancy, the traditional tungsten bulb puts out light in a 360-degree x/y/z axis, a whole ball of light that bounces around, some wasted, some not. The LED replacement for it often has light that is only directed to a half-sphere "down" or "out" from the bulb. If the bulb is installed in a directional application, that may be a good thing, kind of like using a reflector spotlight to get more "brightness" from the same wattage.

If you were planning to hang it on a bare wire in mid-air, not so good, because half the light isn't there.

A lot of folks are spending a lot of R&D money on LED replacements for household bulbs. I don't think they're anywhere near ready yet. Still a LOT of bucks, with a limited light pattern, from what I've seen.

BTW, this is why the COLREGS get way more clever than we give them credit for, by simply asking "Can you see it from xx miles away? over these many degrees?"

[ebs001]

Here's a price comparison of various light sources. I cannot get it as a chart so read it top to bottom under each heading ie incandescent/$2(19)/60/660/11etc

Cost Comparison




Incandescent

Halogen

Fluorescent

LED (Generic)

LED (Philips)

LED (Philips L-Prize)



Purchase price

$2[19]

$4[20]

$4[21]

$20[18]

$25[22]

$50[23]



Electricity usage

60 W

42 W

13 W

9 W

12.5 W

10 W



Lumens

660

570

660[24]

900

800

940



Lumens/Watt

11

13.6

50.8

100

64

94



Color Temperature Kelvin

2700

3100[25]

2700

3000

2700

2700



CRI

100

100

82

>75[26]

85

92



Lifespan (hours)

2,000

3,500

8,000

25,000

25,000

30,000



Bulb cost over 10 years – @6hours/day

$21.90

$25.03

$10.95

$17.52

$21.90

$36.50



Energy cost over 10 years – @15cents/kWhr

$197.10

$137.97

$42.71

$29.57

$41.06

$32.85



Total

$219.00

$163.00

$53.66

$47.09

$62.96

$69.35



Comparison based on 6 hours use per day (21,900 hours over 10 yrs)

[Trekka]

I have 4 of the edison base lamps with clap on shades in my boat. I switched from the screw in tungstn to CFL's even tho that made mounting shades more difficult. After buying a couple at marine stores I found I could order them online from RV companies at half the cost, and with a variety of wattage and color temperatures. The cheaper RV CFL's were sensitive to polarity, and I wound up wire swapping on 3 of the bases. These 12v CFL's worked great, cutting power usage down by at least half while staying bright. A significant reduction but more was desired.

I have tried 2 different 12v LED Globe lamps with the edison screw base. Both have been expensive $30+ , had poor color temperatures (what I call jaundice lighting), and were dim. No way in hell they matched the claimed brightness of 40 or 60 watt bulbs.

My advice, buy where you can return.

There are some very nice DR LED warm white clusters that are made for bayonet bases. If the company mounted one on a screw base and stuck a globe over it would make a very fine lamp for the need.